Tag: earth

Louisiana State University’s Dr. Christopher C. Austin made an itsy-bitsy, yet monumental discovery. His team found two new species of frogs, one of which is the tiniest vertebrate known to man. The previous record had been held by a small Indonesian fish. The tiny discovery was made during a three month long excursion to the tropical island of Papua New Guinea. Though the discovery was made in 2009, the findings were recently published in the Journal PLoS One.

When I say itsy-bitsy I mean tiny enough to fit on the tip of your finger. The frogs belong to the genus Paedophryne, which sports the smallest frogs in the world. The smallest of the two they named Amauensis after Amau Village in the Central Province of New Guinea. The tiny polliwog has an average measurement of 7 millimeters long. You can see this little guy pictured below, sitting on a dime.

Paedophryne Amauensis sitting on a dime (Courtesy of PLoS One)

The second of the two newly discovered species they named Swiftorum after the Swift family who funded the Kamiali Biological Station where the species was found. It is only slightly larger than its record-breaking cousin with an average size of 8.5 millimeters. You can see Swiftorum pictured below, in his natural habitat.

Swiftorum sitting in the wild. (Courtesy PLoS One)

Locating the frogs was not an easy task. Dr. Austin and graduate student Eric Rittmeyer, were intrigued by high pitched calls they were hearing on the forest floor. After several attempts to pinpoint the location of the sound, they decided to scoop up a bunch of leaf litter and bag it up. They then proceeded to search through the litter leaf by leaf until the tiny frog revealed itself. They were caught a little by surprise as they expected it to be an insect. Leaf litter on the forest floor provides essential moisture for these little guys to survive. It seems mini frogs have a tendency to dry out easily. According to the PLoS One publication, “this may explain the absence of diminutive frogs from temperate forests and tropical dry-forests, where the leaf litter is seasonally dry”.

This is a significant find because until recently, extreme sizes in nature were thought to be mostly supported in aquatic environments. For instance, the smallest known vertebrate before this discovery was a fish and the largest known is the blue whale. This led scientists to believe that extreme sizes were a result of buoyancy. Neither of these frogs live in water so this discovery challenges that notion.

Charles Caleb Colton once said, “Imitation is the sincerest form of flattery”. Some people like to mimic for entertainment, but animals do it for survival! The Mimic Octopus has long been known for its ability to transform its looks to protect itself from predators. However, Godehard Kopp, of the University of Gottingen in Germany, caught on film an unlikely partnership between a Mimic Octopus and a Black-Marble Jawfish. It appears that the Jawfish actually mimicked the Octopus as it changed colors.

Jawfish Mimics Octopus Banding (Courtesy Journal Coral Reefs)

The footage was taken on a dive in Indonesia. While it is not unusual to see the Mimic Octopus venture out under the guise of its own camouflage, seeing the Jawfish venture out was quite unusual. They are not very good swimmers and typically don’t venture out of the burrows they make in the sand. It appears that this one used “opportunistic mimicry” to transform its own colors to match that of the Octopus. This allowed the little guy to venture out, presumably to forage for food away from the confines of its burrow.

In the image below, notice how the Black-Marbled Jawfish makes itself appear to be a tentacle streaming from the Mimic Octopus. This is a great camouflage job because the Octopus is mimicking a deadly Lionfish pattern so that no predators will want to come its way.

Notice how the Jawfish looks like a tentacle.

Check out the video of the encounter below.

The ability that this Jawfish shows is unique and is not seen in its Japanese counterparts. For this reason, scientists believe this is opportunistic rather than obligate mimicry. A discovery like this shows how unique and diverse life can be in these coral reefs. Hopefully more can be done to protect this treasure.

For more information about this discovery, the original publication can be seen here.

The International Union for Conservation of Nature (IUCN) declared the Western Black Rhino officially extinct after a recent assessment of several rhinoceros species. Two other subspecies of rhino were also on the brink of extinction. It’s a sobering reminder of the fragility of life. Despite conservation efforts, the IUCN reports that 25% of the world’s mammals are at risk of extinction. The IUCN blames the extinction on a “lack of political support and will power for conservation efforts in many rhino habitats”. Whatever the reasons, the reality is that we lost a beautiful animal never to be seen again with human eyes.

Courtesy Nowpublic.com

‘We are responsible for protecting the species’

Simon Stuart, Chair of the IUCN Species Survival Commission, said, “Human beings are stewards of the earth and we are responsible for protecting the species that share our environment.” This appears to be a difficult message to get across, especially when you consider how much illegal poaching of animals still occurs. It is especially frustrating to think that these extinctions were preventable. Stuart went on to say. “In the case of both the Western Black Rhino and the Northern White Rhino the situation could have had very different results if the suggested conservation measures had been implemented.”

‘A Glint of Hope’

There is a glint of hope in the midst of these tragedies. When conservation programs are put into place, wonderful things can happen. For example, the Southern White Rhino was thought to have a population of less than 100 at the end of the 19th century. Due to conservation efforts, that population has increased to over 20,000. Przewalski’s horse (pictured below) is another success story. Back in 1996, the horse was considered extinct in the wild. Now there are as many as 300 known to exist.

Courtesy Wikipedia

Such a widespread and overwhelming issue can make one feel powerless to help. However, if we, as individuals, do what we can, things can get better. A great place to start, that is often overlooked, is your local zoo. I am proud to say that my local zoo, The Lousiville Zoo, played a part in the comeback of the Southern White Rhino due to its participation in the Species Survival Plan. Supporting reputable organizations such as these is simple. You don’t have to be a millionaire to make a difference, either. Just get involved. Even if it is simply volunteering to teach children, you never know when that child might become the politician who influences conservation policy, or the billionaire developer that develops with the environment in mind.

It is my hope that, in some small way, my words today will inspire someone to do more to be a better steward of the world in which we live. To me, it isn’t about politics or activism. It’s about everyday people taking a moment to step back and think about how their actions affect the world at large. Our world has lost a wonderful creature. Take a moment today and do something worthy in its honor. Remember, humans are mammals too.

Listed below are a couple of links to organizations where you can learn more about conservation efforts and how you can help.

A conclusive study on climate and its impact on the rise of sea level is out and the results are quite grim. An international team of researchers, including many from the University of Pennsylvania, has put forward incriminating data acquired through decades that unambiguously points to a direct correlation between increase of ocean surface temperature and the rise of global sea-levels.

The Team

The study is led by Benjamin Horton, associate professor and director of Sea Level Research Lab, in collaboration with Andrew Kemp and Michael Mann, the man who first came up with the famous hockey-stick graph (see below). It is funded by the National Science Foundation among other institutes and boasts of many scientists from institutes like University of Pennsylvania, United States Geological Survey and the National Oceanic and Atmospheric Administration.

The famous Hockey Stick Graph by Michael Mann. The black line represents

This is the first complete continuous sea-level reconstruction for the past 2000 years. The trends have been compared with signs of global temperature increase and the positive correlation is too overwhelming to ignore.

Results

The study finds that from 100 BC to 950 AD, the oceanic temperature was stable and so was the sea-level. For the next 400 years, the sea level rose by half a millimetre every year on average. This period in human history, called the Medieval Climate Anomaly, saw a steady rise in annual temperatures globally. Temperatures stayed cool and stable till the 19th century after that medieval period. However, since the late 19th century and, especially in the 20th century, sea-levels have risen on average by an alarming 2mm per year, surely one of the highest rates in the entire of Earth’s history. Again, a direct correlation with temperature rise was noted.

Methodology

The team did a thorough job with the research. They used micro-fossils called foraminifera as markers. Found in sedimentary rocks, they respond in quantitatively measurable ways to change in the salinity of the water they live in. By drilling into the sedimentary rock, fossils from different ages can be studied. Bear in mind that, since, sedimentary rocks stack up in layers, drilling deeper means that we are effectively looking at older rocks a sort of geological time capsule. The samples, taken mainly from the marshes in North Carolina, can be dated by using radiocarbon dating techniques on the rocks in which it is found. A check on the dates was provided by a complimentary technique the Potassium-Argon dating method. Core samples equivalent to 2000 years were dug up.

Two typical foraminifera fossils; these are used extensively for radiocarbon datingA typical core sample taken from sedimentary rock layers

This is much less than the core samples dug up from the Arctic, but the markers in the Arctic snow are much less useful. However, both tell essentially the same story, pointing to the same direct correlation.

The team accounted for effects of hurricanes that generally rearrange sedimentary layers by taking samples from places that face away from the sea. Hurricane imprints are easy to read, as the sedimentary rocks show unusually high amounts of sand blown in from the sea. The team also accounted for vertical land movements that will show a parallax in the sea-level rise data.

Horton says:

It’s evidence to support the obvious. The basic laws of physics say if you increase temperature, ice will melt. But what we show is how sensitive sea level is to changes in temperature

This study disappoints in only one respect it doesn’t predict any trend for the near future. However, climatologists are already mulling the option of extrapolating the data to see if it fits.

Kemp points out:

Scenarios of future rise are dependent upon understanding the response of sea level to climate changes. Accurate estimates of past sea-level variability provide a context for such projections

A cleavage seen in the Antarctic ice-shelf with fresh water running down into it. The people provide the scaleIs this paranoia or the future?

The Last Word

The trend is disturbing. Carbon dioxide levels are rising, undoubtedly due to human activities. Now with this study confirming the worst, nations must take the imperative to bring their individual carbon footprints out. Skeptics may object, but it will take more than mere objections and fault-finding to get around this report. Silent numbers and dumb graphs speak louder than verbose microphones.

There is simple science behind the quake that shook Japan recently and those that have occurred throughout Earth’s history. We consider here, only those earthquakes that are caused by forces arising from beneath the earth’s surface, commonly called tectonic forces.

Our earth’s crust is broken up into many fragments, all floating on semi-solid magma in the mantle of the earth. These fragments, called tectonic plates, are thus capable of moving, albeit very slowly and just a bit each year. Stress can build up along the edges between the plates if one cannot move against the other. Earthquakes are caused by tectonic plates suddenly sliding on each other at edges where they meet. The earth shakes as huge amounts of energy are released into the surrounding medium.

There are two types of waves by which energy is transferred. One is called the primary or P wave, the other, secondary or S wave. They are also fundamentally different. The P wave travels much faster than the S wave. The P wave travels by compressing the ground at certain points and stretching it out at some other points, just like sound waves in air. This mode is called the longitudinal mode. The S wave travels by undulating the ground in the direction perpendicular to the propagation, like light waves. This mode is called the transverse mode.

Longitudinal and Transverse Waves

Locating the epicenter: How do scientists know where the center of the earthquake (the epicenter) is? Since the P wave travels faster than the S wave, it arrives at a certain place before the S wave. Places nearer the epicenter will experience the two in quick succession and far off places will experience a greater delay between the two waves. Using delay data from different earthquake monitoring centers, one can triangulate the position of the epicenter and even track how far below the earth’s surface it lies.

Measuring an earthquake: What does a “magnitude 7 earthquake on the Richter Scale” mean? The Richter scale magnitude measures how much the earth shakes. It does so by considering how much the needle of the seismograph (figure below) oscillates.

Seismograph

The Richter scale is a logarithmic scale. This means that a 5 magnitude earthquake is 10 times as powerful (causes 10 times more shaking on the seismograph) than a 4 magnitude quake. A 6 magnitude one is 10 times as powerful as a 5 magnitude one and 100 times as powerful as a 4 magnitude one.

Earthquakes are often followed by smaller ones called aftershocks, (and sometimes, preceded by ‘foreshocks’). This happens because the earth restores itself and takes some time to do so.

Prediction of earthquakes is impossible with the current technology and will likely remain so for a very long time. As far as data suggests, earthquakes are completely random and no occurrence pattern has ever been observed. As to whether animals can really sense’ earthquakes before they happen is a matter of speculation.